Motherboard manufacturers can distribute the PCIe lanes in many configurations, including four PCIe 2.0 x16 slots with eight-lane signaling. With all 41 PCIe 2.0 lanes, the RD790 chipset has a TDP up to 10-watts. AMD roadmaps reveal the multiple PCIe 2.0 slots are used for an improved CrossFire multi-GPU technology. The improved CrossFire multi-GPU technology supports up to four ATI Radeon HD 2900 XT graphics cards in Quad CrossFire configurations.

Unlike NVIDIA’s SLI, which supports dual or quad graphics cards in SLI, the improved CrossFire solution can take on three cards for improved performance. AMD claims CrossFire scaling with three cards yields a 2.6x performance increase. Two cards in CrossFire yield a 1.8x performance improvement. AMD roadmaps do not divulge how well CrossFire scales with four GPUs.

Expect RD790 to arrive later this year in time for the AMD Phenom product launch in single and dual processor configurations.

"Well, there may be a reason why they call them 'Mac' trucks! Windows machines will not be trucks." -- Microsoft CEO Steve Ballmer